Sulfo-acid ester and process of making same.



fr HE IE DIAIES GEN SAPPER AND FRIEDRICH REUBOLD, OF LUDWIGSHAFEN-ON-THE- DRAFTSMAR Patented July 19, 1904.

PATENT OFFICE.

RHINE, GERMANY, ASSIGNORS TO BADISOHE ANILIN UND SODA FABRIK,

OF LUDWVIGSHAFEN-ON THE-RHlNE, GERMANY,

BADEN.

SULFO-ACID ESTER AND PROCESS OF MAKING SAME.

SPECIFICATION formingpart of Letters Patent No. 765,597,

Application filed August 2'7, 1903.

T0 aZZ whom, it 72110.3 concern.-

Be it known that we, EUGEN SAPPER, doctor of science, and FRIEDRICH REUBoLD, doctor of philosophy and chemist, subjects of the King of Bavaria, residing at Ludwigshafenon-the-Rhine, in the Kingdom of Bavaria, Empire of Germany, have invented new and useful Improvements in Sulfo-Acid Esters and Process of Making the Same, of which the following is a specification.

e have invented a new process for preparing bodies of the general formula cox I osoza where X denotes hydrogen or hydroXyl and R an aryl radical.

The process consists in treating under suitable conditions the esters of cresols and aryl sulfo-acids of the general formula ora 4 osoza with manganese dioXid and sulfuric acid, whereby sulfo-acid esters of hydroxybenzaldehyde or hydroxybenzoic acid, or both, result. These compounds can be converted by saponification into the corresponding hydroxybenzaldehydes or hydroxybenzoic acids and an aryl sulfo-acid. They are practically insoluble or difficultly soluble in water; but they are soluble in alcohol and ether. The saponification of the said compounds can be effected in any suitable known mannerfor instance, by treatment with concentrated sulfuric acid in the cold or on gently warming or by boiling with-caustic-soda lye.

The aforementioned estersnofcrie sols and aromatic sulfo-acids can be obtained by the action of an aryl sulfochlorid-esuch as benzene-sulfochlorid, para-toluene-sulfochlorid, or ortho-toluene-sulfochlorid-on an aqueous solution of a cresol in Warm dilute causticsoda lye according'to the method of Schotten and Baumann, and they can generally be obtained in crystalline form from ethyl alcodated July 19, 1904.

Serial No. 171,018. (Specimens) 1101. Some of the sulfo-acid esters of hydroxybenzaldehydes which can be obtained by the new process are known; but it also yields a large number of new products, and in particular those obtained when using toluenesulfochlorid are new and possess a high value.

The following example will serve to further illustrate the nature of our invention; but it is not confined to this example. The parts are by weight:

Example: Heat together at the temperature of the boiling-water bath, while stirring Well, five hundred parts (500) of toluene sulfo-acid esterof orthocresol with eight hundred (800) parts of sulfuric acid containing from seventy to eighty (7 O to 80) per cent. of H2804 and three hundred (300) parts of finelyground manganese dioxid. Owing to the heat of the reaction, the temperature of the reaction mass generally rises at first above one hundred degrees centigrade (100 C.) After stirring for from four to five (i to 5) hours at the temperature of the boiling-water bath di- A CORPORATION OF lute the contents of the vessel with about nine hundred (900) parts of water and allow the whole to stand in a warm place. The product of the reaction separates out as an oil. Separate it from the aqueous layer and the manganese mud in any convenient manner and well mix it with a cold dilute solution of caustic soda. Filter and acidify the filtrate. The toluene sulfo-acid ester of salicylic acid is precipitated. Stir up the reaction product remaining undissolved with two hundred and fifty (250) parts of sodium-bisulfite solution containing about forty (40) per cent. of NaHSOg, thereby converting the aldehyde into its bisulfite compound. Dissolve it by the addition of Water and filter it or separate it in any convenient manner from unaltered cresol ester. To the filtered bisulfite solution add acid or alkali, whereby the toluene sulfo-acid ester of salicylic aldehyde is precipitated, generally as an oily mass, which, however, soon solidifies to crystals. It can be purified by recrystallization from alcohol. The unaltered cresol ester can be employed for another operation. In a similar manner the oxidation of other cresol can be varied within certain limits. A greater dilution of the acid, for example, can be compensated for by the employment of a larger quantity of it or by raising the temperature. The best conditions for each single case must be determined by experiment.

We claim- 1. The process of manufacturing bodies of the hereinbefore-explained general formula C H GOX G osozn by treating the cresol esters of aryl sulfoacids with manganese dioxid and sulfuric acid. 2. The process of manufacturing bodies of the hereinbefore-explained general formula COX soon? by treating the cresol esters of para-toluene sulfo-acid with manganese dioxid and sulfuric acid.

3. The process of manufacturing bodies of the formula OOH OSO2C7H1 by treating the cresol esters of para-toluene sulfo-acid with manganese dioxid and sulfuric acid.

" witnesses.

4. The process of manufacturinga body of the formula CH /COH 1 6 osoonq (2) by treating the orthocresol ester of para-toluene sulfo-acid with manganese dioXid and sulfuric acid.

5. As new articles of manufacture, the bodies of the formula con o6Hi osozcat which are white crystalline bodies, which are diificultly soluble in water, but are easily soluble in ether and in hot alcohol, which melt below a temperature of 100 centigrade and which on saponification yield para-toluene solfo-acid and hydroxybenzaldehyde.

6. As a new article of manufacture, the body of the formula CH coH 1 b 4 oso2c7n7 2 which is a white crystalline body, which is diificultly soluble in water, but is easily soluble in ether and in hot alcohol, which melts below a temperature of 100 centigrade, and which on saponification yields para-toluene sulfo-acid and ortho-hydroxybenzaldehyde.

In testimony whereof we have hereunto setour hands in the presence of two subscribing EUGEN SAPPER. FRIEDRICH REUBOLD.

Witnesses:

JAooB ADRIAN, H. YV. HARRIs. 

